Incident Details
On August 5, 2013, at approximately 1800 Alaska daylight time, a McDonnell Douglas/Hughes 500D helicopter, registration N134SH, was substantially damaged in an accident near Delta Junction, Alaska. The helicopter was operating under Title 14 Code of Federal Regulations Part 133 as an external load flight. The pilot, who was not injured, was transporting sections of water hose to a remote site using a 100-foot-long external load line attached to the helicopter's belly-mounted cargo hook.
The pilot reported that while hovering about 100 feet above the intended drop site and about 5 to 10 feet above trees, facing into a hill, the engine lost all power. The pilot then initiated an emergency hovering autorotation and turned the helicopter left in an attempt to face it downhill. Subsequently, the helicopter settled into trees, during which the main rotor blades struck several trees. The helicopter then impacted terrain hard and rolled onto its right side, resulting in substantial damage to the main rotor drive system, tailboom, and fuselage.
Postaccident Examination
During the postaccident examination, approximately 60 pounds of fuel (47 pounds usable) were drained from the helicopter's fuel cell. An engine test-run demonstrated that the engine produced full rated power at various power settings. A subsequent test-run showed that the electric fuel pump operated within its operating specifications. Examination of the fuel pump revealed wear on the motor commutator and brushes. The postaccident examination of the helicopter found no preaccident mechanical malfunctions or failures that would have precluded normal operation.